The measured ability of any amplifier to isolate incoming power supply noise and disturbances from the load has obvious sonic and economic benefits. To meet this objective, analog amplifiers employ many techniques, such as heavily-filtered bias supplies and differential drive.
Switching amplifiers, particularly those with saturated output switching devices connected directly to the incoming power supply, have proven more intractable to improvements in this area; in that the supply is switched directly to the load. A need exists for a technique through which power supply rejection of incoming disturbances can be improved in switching amplifiers.